Each week, I devote part of my Sunday to reading.  I tend to accumulate a lot of saved links on Facebook during the week, and I like to try to keep up with what fellow writers are posting here on WordPress.  At the end of my reading day, I like to put up a post to draw my readers’ attention to a few articles I found to be of particular interest.

Here’s what I enjoyed this week:

Where to search for signs of life on Titan

by Julia Demarines, Astrobiology Magazine

With its dense atmosphere and seas of liquid methane, Saturn’s moon Titan is truly unique in our solar system.  Or at least almost unique, as for years scientists have noted there is one planet in our star system that bears a striking resemblance to Titan: Earth.  While the similarities might not be so easily observed today, research suggests that in its infancy our planet was likely far more similar to Titan than to the world we know today.  For scientists, that offers the tantalizing prospect of finding the building blocks of life on a distant moon, and perhaps life itself.

Of course, there is one marked difference between Earth and Titan: Titan is very, very cold.  But a recent study led by Dr. Catherine Neish of the University of Western Ontario suggests the extremely low temperatures on Titan may not fully rule out the possibility of life after all.

Hopes for finding life on Titan have been bolstered by recent analysis of data complied by the Cassini space probe, which orbited Saturn for over a decade, as well as observations from the ESA Huygens probe, which landed on the surface.  Data suggests that the surface of Titan is geologically active, either due to erosion or cryovolcanic activity.  And the presence of cryovolcanoes may signify the presence of life.

While the surface of Titan is rich in hydrocarbons, heat and water are necessary to form amino acids, which could lead to the formation of proteins and, ultimately, living cells.  To that end, Neish and her colleagues suggest searching in craters, where water from cryovolcanoes might collect without immediately refreezing (she also noted that high concentrations of ammonia in the water would help).

You’re living in a new geologic age. It’s called the Meghalayan

by Beth Geiger, Science News

Earth has been around for a while.  Four-point-six billion years or so, in fact, and a lot’s happened.  Luckily, much of that vital and fascinating history of our tiny world has been preserved in the geological record.  That includes the history we’re making right now, as Beth Geiger wrote for the Science News this past week.

The geological record is arguably the most valuable direct evidence we have of Earth’s past.  While perhaps not so well-known as the fossil record, as life has not always existed on Earth (or always existed in a form capable of being fossilized), the geological record stretches back further than the earliest fossils.  What’s more, the geological record can also tell us things fossils cannot, helping to shed light on the crucial earliest moments of the incredible planet that would become our home.

The process by which Earth’s geological record is formed; the slow accumulation of sediment and igneous formations, the transformation through heat and pressure of one form of mineral into another, is ongoing, and it’s happening even now.  Based on recent analysis, geologists have separated our current geological epoch, the Holocene, into three distinct ages.  This is remarkable in many ways, perhaps foremost because we are now capable of watching a geological age in progress, witnessing formative events firsthand.

In our case, our current age, the Meghalayan, began roughly 4,200 years ago with a global drought that lasted two centuries.  This drought caused severe famine and food shortages across the planet, likely leading to the fall of several powerful civilizations, most notably the Indus Valley Civilization, the Akkadian Empire in Mesopotamia, and the Old Kingdom of Ancient Egypt.

The significance of this is difficult to overstate.  After years of digging and studying, we humans are now watching the history of our planet continue to unfold.  Our current period has seen rises in global temperatures reflected in sediments future generations may well study, and while we used the fossil record to expand the story of Earth’s geological history, future generations may well use the archaeological record in the same way.  Perhaps, in reading articles like this one, more of us will come to appreciate our role in our planet as a hole, and our nature, for better for worse, as little more than a blip upon an endless line.

This oven was used to make bread—thousands of years before agriculture

by Michael Price, Science

In one of the most earth-shattering stories this past week, a group of researchers from the University of Copenhagen announced the discovery of early bread making in Jordan, outlined in brief in this article by Michael Price of Science.

Through the use of electron microscopes, the researchers were able to find evidence of bread fragments in a 14,500 year old hearth, suggesting the fireplace had been used for baking.  The bread was a simple flatbread, made by grinding, sifting, and kneading either Einkorn wheat, oat, or barley before baking (the product was likened to many simple flatbreads found at later neolithic and Roman sites, and was said to be similar to Mediterranean pita).

While it’s remarkable to see how little the process of break making has changed in some ways, the discovery was groundbreaking as it seems to rewrite the history of both food preparation and agriculture.  While no doubt there were early experiments in domesticating plants, human agriculture began in earnest roughly 10,000 years ago…over four thousand years after the bread found in this hearth was baked.  Previously, it was generally assumed that complex foods like bread, which is very labor-intensive, were developed after agriculture began (possibly as a consequence of an abundance of grain that was easily harvested).  This new discovery, combined with stone tools found at the site resembling grinding implements and scythes, may suggest that the desire to produce more bread may have ultimately led to agriculture, not vice-versa.

For those interested in more information on this story, a piece produced by the University of Copenhagen can be found here.

 

Knowledge is power.  Take time out to read each week.  It’s your window into the world around you.